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WASHINGTON — With his first 50 pitches, Sean Manaea cruised and struck out eight batters. 

With his last 41 pitches, Manaea crumpled and struck out zero. 

Not everything from an outing in which he was charged with four runs on three hits, a walk and two hit batters in 4 ²/₃ innings can be blamed on the lefty, but Manaea continues to be less effective the deeper he pitches in games. 

“Deeper” is relative for a starter who has not yet completed six innings in any of his eight starts since being activated from the injured list. 

Manaea’s stuff teased until it tapered off again Thursday, when he looked wondrous then wild in a disappointing 9-3 loss at Nationals Park. 

“He gets to that fifth inning and it’s either [losing] the strike zone or they’re right on the fastball,” manager Carlos Mendoza said of Manaea, who owns a 5.15 ERA this season after emerging as a 2024 revelation. “But again, as a starter, you got to find a way to get through at least five. And right now we’re not getting that.” 

After an oblique strain and a loose body in his elbow kept him sidelined until mid-July, Manaea has returned but has not looked like last year’s version — the most noticeable dip arriving later in games. 

His overall velocity is down this season, but he also is losing it and losing control throughout the game. 

“I wouldn’t say fatigued — I feel good,” said Manaea, who has faced 20 hitters this season when a lineup has turned over a third time and allowed 10 of those hitters to reach base. “I really have no explanation for why I’m hitting that wall.” 

Once more, Manaea was dominant — striking out five on just 22 pitches (17 strikes) through two perfect innings — before he was dented in the fourth and fifth innings. 

On this afternoon at least, he pitched better than his final line.

The Nationals scored once in the fourth, when CJ Abrams struck out but took first base when the sweeper bounced past Hayden Senger and to the backstop.

Abrams would come around to score. 

In the fifth, Manaea let up a single to Brady House before Jacob Young attempted a sacrifice bunt.

Pete Alonso grabbed the ball and threw to second base too late, getting no outs on the play.

His defense having let him down, Manaea could not navigate out of danger: He drilled Abrams, allowed a one-out sacrifice fly to Paul DeJong and walked Andrés Chaparro to load the bases. 

“Just lost feel for my sweeper right there, then just lost control of my fastball at the end there, too,” said Manaea, who watched Tyler Rogers enter and give up a two-run single to Riley Adams. 

Manaea struggling for both length and results is a problem.

That problem mushrooms because Kodai Senga is dealing with the same issues, and Clay Holmes has not recorded 18 outs in a start since June 7.

Frankie Montas already has pitched his way out of the rotation. 

“At this point, with everybody [in the rotation] pretty much healthy,” Mendoza said, “we need to be better.”